4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Oliver Hartkopp <socketcan@xxxxxxxxxxxx>
commit a43608fa77213ad5ac5f75994254b9f65d57cfa0 upstream.
When the socket is CAN FD enabled it can handle CAN FD frame
transmissions. Add an additional check in raw_sendmsg() as a CAN2.0 CAN
driver (non CAN FD) should never see a CAN FD frame. Due to the commonly
used can_dropped_invalid_skb() function the CAN 2.0 driver would drop
that CAN FD frame anyway - but with this patch the user gets a proper
-EINVAL return code.
Signed-off-by: Oliver Hartkopp <socketcan@xxxxxxxxxxxx>
Cc: linux-stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/can/raw.c | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)
--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -745,18 +745,19 @@ static int raw_sendmsg(struct socket *so
} else
ifindex = ro->ifindex;
- if (ro->fd_frames) {
+ dev = dev_get_by_index(sock_net(sk), ifindex);
+ if (!dev)
+ return -ENXIO;
+
+ err = -EINVAL;
+ if (ro->fd_frames && dev->mtu == CANFD_MTU) {
if (unlikely(size != CANFD_MTU && size != CAN_MTU))
- return -EINVAL;
+ goto put_dev;
} else {
if (unlikely(size != CAN_MTU))
- return -EINVAL;
+ goto put_dev;
}
- dev = dev_get_by_index(sock_net(sk), ifindex);
- if (!dev)
- return -ENXIO;
-
skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv),
msg->msg_flags & MSG_DONTWAIT, &err);
if (!skb)
